Select Xml Node using Linq to XML

Question

my Xml file :

Answer 1

Your problem is that Descendents and Where return an IEnumerable<XElement> not a single XElement which is what you're after. You can fix this like this:

XElement toEdit = doc.Descendants("ArrayOfCustomer")
                     .Descendants("Customer")
                     .Where(x => Guid.Parse(x.Descendants("CustomerId").Single().Value) == customer.CustomerId)
                     .FirstOrDefault();

Answer 2

I would restructure your query like this:

 XElement toEdit = doc.Descendants("Customer")
                      .Where(x => (Guid)x.Element("CustomerId") == customer.CustomerId)
                      .FirstOrDefault();

Answer 3

You are not casting x you are casting x.Descendants(). x.Descendants() returns a collection, hence the plural method semantic. Off the top of my head you should be able to do x.Descendants("CustomerId").FirstOrDefault() as XElement

Answer 4

XElement toEdit = (from c in doc.Descendants("Customer")
     where Guid.Parse(c.Value) == customer.CustomerId
     select c).SingleOrDefault();